• Economic and Environmental Geology
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• v.41 no.1
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• pp.15-32
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• 2008

The hydrochemical and isotopic (stable isotopes and noble gas isotopes) analyses for hot spring waters, cold groundwaters and surface water samples from the Seokmodo hot spring area of the Ganghwa province were carried out to characterize the hydrogeochemical characteristics of thermal waters and to interpret the source of thermal water and noble gases and the geochemical evolution of hot spring waters in the Seokmodo geothermal system. The hot spring waters and groundwaters show a weakly acidic condition with the pH values ranging from 6.42 to 6.77 and 6.01 to 7.71 respectively. The outflow temperature of the Seokmodo hot spring waters ranges from $43.3^{\circ}C\;to\;68.6^{\circ}C$. Relatively high values of the electrical conductivities which fall between 60,200 and $84,300{\mu}S/cm$ indicate that the hot spring waters were mixed with seawater in the subsurface geothermal system. The chemical compositions of the Seokmodo hot spring waters are characterized by Na-Ca-Cl water type. On the other hand, cold groundwaters and surface waters can be grouped into three types such as the Na(Ca)-$HCO_3$, Na(Ca)-$SO_4$ and Ca-$HCO_3$ types. The ${\delta}^{18}O\;and\;{\delta}D$ values of hot spring waters vary from -4.41 to -4.47%o and -32.0 to -33.5%o, respectively. Cold groundwaters range from -7.07 to -8.55%o in ${\delta}^{18}O$ and from -50.24 to -59.6%o in ${\delta}D$. The oxygen and hydrogen isotopic data indicate that the hot spring waters were originated from the local meteoric water source. The enrichments of heavy isotopes ($^{18}O\;and\;^2H$) in the Seokmodo hot spring waters imply that the thermal water was derived from the diffusion Bone between fresh and salt waters. The ${\delta}^{34}S$ values ranging from 23.1 to 23.5%o of dissolved sulfate are very close to the value of sea water sulfate of ${\delta}^{34}$S=20.2%o in this area, indicating the origin of sulfate in hot springs from sea water. The $^3H/^4He$ ratio of hot spring waters varies from $1.243{\times}10^{-6}\;to\;1.299{\times}10^{-6}cm^3STP/g$, which suggests that He gas in hot spring waters was partly originated from a mantle source. Argon isotopic ratio $(^{40}Ar/^{36}Ar=298{\times}10^{-6}cm^3STP/g)$ in hot spring waters corresponds to the atmospheric value.

• The Journal of the Petrological Society of Korea
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• v.24 no.3
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• pp.181-191
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• 2015

The Bakseok of Geunjeongjeon Hall in Gyeongbokgung Palace is platy floor stone acting as drainage, protected glaring and sliding. The Bakseoks were composed of anisotropic medium-grained biotite granite with a weak myrmekitic texture. Interpretation of transportation process for the Bakseok and original granite provenance trace of and analyze of identity based on ancient writings and detail field survey. As a result, the very similar granite with the Bakseok in lithology, composition mineral, texture and geochemical characteristics was found around Mt. Nakgasan in the Seokmodo Island. There were interpreted stonework process of the Bakseok used exfoliation granite dome with physical weathering properties in Seokmodo Island, to get platy stone economically stonework at the state level as a minimized on burden of supply and men power.

• The Journal of the Petrological Society of Korea
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• v.15 no.2 s.44
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• pp.60-71
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• 2006

The Seokmodo consists mainly of biotite granite and granodiorite. The biotite granite is divided into the south and the north part by granodiorite. There occurs high temperature hot spring of which temperature is up to $72^{\circ}C$. The Rb-Sr isotopic data for the biotite granite define whole-rock isochron ages of $207{\pm}70$ Ma with initial Sr isotopic ratio of 0.7132 in north part and $132{\pm}50$ Ma with initial Sr isotopic ratio of 0.7125 in south part, suggesting that the magma be derived from the crustal source material. The geochemical characteristics of the biotite granite and hornblende granodiorite indicate that they were crystallized from calc-alkaline under syn-collisional tectonic environment. The samples of hot spring were collected at March 2005 and March 2006. The $^{87}Sr/^{86}Sr$ ratios of hot spring are 0.714507 and 0.714518, respectively and correspond to those oi the granite being occurred at the south part. The similarity of $^{87}Sr/^{86}Sr$ ratios between the granite and hot spring strongly suggests that the hot spring might be derived from the Seokmodo biotite granite.

• 한국지구물리탐사학회:학술대회논문집
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• 2010.10a
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• pp.165-166
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• 2010

• Korean Journal of Plant Resources
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• v.35 no.2
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• pp.201-241
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• 2022

This study was investigated distributed the vascular flora of around Haemyeong Mt., located in Seokmodo, Incheon, and compared invasive alien plants in the surrounding forest 14 areas. This study carried out to be established a monitoring system for the remarkable plants etc. and used as basic data for biodiversity enhancement and conservation. The survey was conducted 19 times from April 2019 to October 2020. A total of 107 families, 382 genera, 616 species, 15 sub-species, 55 varieties, 8 formas, and 694 taxa were classified in the flora around Haemyeong Mt. areas. 17 taxa for Korea endemic plants. 12 taxa were classified for rare plants, and a total of 79 taxa were identified for floristic target species I~V. Halophytes consisted of 37 taxa. The invasive alien plants were classified as 66 taxa, and also there has been 126 taxa of them in Seokmodo and surrounding 14 forests. Plants that appeared in all 14 areas out of 126 taxa were classified as 7 taxa, such as Erigeron annuus. However, 48 taxa appeared only once in some areas, but it seems inevitable that they will spread in the future. Therefore, it is necessary to prepare a long-term conservation plan for native plants.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.5
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• pp.344-351
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• 2010

Uncertainty analysis on the net flow discharge (NFD) influencing the long-term material transport and the simulation results of the salinity and COD concentration distribution using the MIKE21 diffusion model in Gyeonggi bay and Han-River estuary is carried out. The NFD flowing the Gyodongdo - Seokmodo channel via the North channel of Ganghwado is estimated about 97% of the total NFD and the NFD of the Yeomha channel is estimated as only $2.5{\sim}3.0%$. On the other hand, the uncertainty defined as the difference by the different time-scale data input is analysed by the comparison of the model simulation result of the salinity and COD concentration distribution. One is computed based on the daily river flow data, and the other is computed based on the monthlymean river flow data. The results show that the salinity and COD concentration differences are about -10~20 psu and ${\pm}1.0\;mg/L$ during the summer season having a high flow discharge in Yeomha channel, respectively. The difference is clearly negligible in the open sea area.